Abstract: A system and method of designing an integrated circuit capable of deriving timing constraints for individual block-level circuits of an integrated circuit that are derived from the chip-level timing constraints and analysis. The block-level timing constraints are in the form of one or more logical timing constraint points at the input and output ports of block-level circuits. Each logical timing constraint points specifies a clock source used to clock data through the port, a delay parameter specifying data propagation delay backward from an input port and forward from an output port, and any timing exception associated with the data path. Using the logical timing constraint point, the circuit design system performs independent timing analysis and optimization of each block-level circuit. The system then reassembles the block-level circuits into a modified chip-level circuit for which timing closure can be achieved.

Abstract: A method of predicting the behavior of software agents in a simulated environment involves modeling a plurality of software agents representing entities to be analyzed, which may be human beings. Using a set of parameters that governs the behavior of the agents, the internal state of at least one of the agents is estimated by its behavior in the simulation, including its movement within the environment. This facilitates a prediction of the likely future behavior of the agent based solely upon its internal state; that is, without recourse to any intentional agent communications. In the preferred embodiment the simulated environment is based upon a digital pheromone infrastructure. The simulation integrates knowledge of threat regions, a cognitive analysis of the agent's beliefs, desires, and intentions, a model of the agent's emotional disposition and state, and the dynamics of interactions with the environment.

Abstract: An adjustable buffer including a series of P-channel devices having current paths coupled between a first voltage supply and at least one output node, and a series of N-channel devices having current paths coupled between the output node and a second voltage supply. The control electrodes of the P- and N-channel devices are coupled to a selected one of an input node and a corresponding voltage supply collectively forming first and second sets of selectable connections. The first and second sets of selectable connections are made to adjust delay from the input node to the output node. The selectable connections may be defined in an integrated circuit mask or may be electronic switches. The P- and N-channel devices may be in a balanced configuration or an imbalanced configuration. The P- and N-channel devices may form an inverting buffer or a non-inverting buffer.

Abstract: A method, system and computer program product for reversing effects of reparameterization is disclosed. The method comprises receiving an original design, an abstracted design, and a first trace over the abstracted design. One or more conditional values are populated into the first trace over the abstracted design, and a k-step satisfiability check is cast to obtain a second trace. One or more calculated values are concatenated to an initial gate set in the second trace with one or more established values to a generated subset of the initial design in the abstracted trace to form a new trace, and one or more effects of a reparameterization are reversed by returning the new trace over the initial design.

Abstract: A cycle basis is efficiently determined for a directed graph. A first depth-first search of the directed graph classifies each of the edges of the directed graph to have a type that is one of a within-tree type for an edge within a tree of the first depth first search, a forward type for an edge skipping forward along the tree, a back type for an edge directed back along the tree, or a cross type for an edge between two subtrees of the tree. A second depth-first search of the directed graph determines a respective cycle for each of the edges of the back type. A third depth-first search of the directed graph determines a respective cycle for each of the edges of the cross type that is included a cycle. The basis is output the basis that specifies each of the respective cycles.

Abstract: A method, system and computer program product for reversing effects of reparameterization is disclosed. The method comprises receiving an original design, an abstracted design, and a first trace over the abstracted design. One or more conditional values are populated into the first trace over the abstracted design, and a k-step satisfiability check is cast to obtain a second trace. One or more calculated values are concatenated to an initial gate set in the second trace with one or more established values to a generated subset of the initial design in the abstracted trace to form a new trace, and one or more effects of a reparameterization are reversed by returning the new trace over the initial design.

Abstract: A design structure for a Duty Cycle Correction (DCC) circuit is provide in which pairs of field effect transistors (FETs) in known DCC circuit topologies are replaced with linear resistors coupled to switches of the DCC circuit such that when the switch is open, the input signal is routed through the linear resistors. The linear resistors are more tolerant of process, voltage and temperature (PVT) fluctuations than FETs and thus, the resulting DCC circuit provides a relatively smaller change in DCC correction range with PVT fluctuations than the known DCC circuit topology that employs FETs. The linear resistors may be provided in parallel with the switches and in series with a pair of FETs having relatively large resistance values. The linear resistors provide resistance that pulls-up or pulls-down the pulse width of the input signal so as to provide correction to the duty cycle of the input signal.

Abstract: A method and apparatus for selecting programmable interconnects to reduce clock skew is described. A routing tree for clock signals is created having routes and clock pin nodes. Delays of the clock signals to the clock pin nodes are determined. The routing tree is balanced to a target clock skew, such as zero clock skew, for the clock signals provided to the clock pin nodes. Programmable interconnect circuits are selectively added to reduce clock skews of the clock signals, where the clock skews being reduced at the clock pin nodes are for at least a portion of the clock pin nodes. Additionally described are determining clock propagation delays to clock pins and balancing a clock tree using computer aided design.

Abstract: A method and system to automate scan synthesis at register-transfer level (RTL). The method and system will produce scan HDL code modeled at RTL for an integrated circuit modeled at RTL. The method and system comprise computer-implemented steps of performing RTL testability analysis, clock-domain minimization, scan selection, test point selection, scan repair and test point insertion, scan replacement and scan stitching, scan extraction, interactive scan debug, interactive scan repair, and flush/random test bench generation. In addition, the present invention further comprises a method and system for hierarchical scan synthesis by performing scan synthesis module-by-module and then stitching these scanned modules together at top-level. The present invention further comprises integrating and verifying the scan HDL code with other design-for-test (DFT) HDL code, including boundary-scan and logic BIST (built-in self-test).

Abstract: Various techniques related to clocking signals used for automated circuit design and simulations are disclosed. In some embodiments, a method includes receiving first and second asynchronous clock signals having a first phase relationship at a first time, and sampling the second clock signal at transitions of the first clock. The method further includes storing the samples; and analyzing the samples to ascertain the first phase relationship of the second clock signal with respect to the first clock signal and provide a representation of the first phase relationship. Other embodiments are described.

Abstract: The invention relates to a method and a system for repartitioning a formalized hardware description of a hierarchically structured electronic circuit design unit comprising a plurality of macros in terms of latch macros and combinatorial macros. In a first step, each macro is dissected into latch macros and signal cones in such a way that each signal cone comprises signals linking macro input/output to a latch output/input, and each latch macro comprises at least one latch, each primary input an output of said latch macro coinciding with an input or an output of a latch within said latch macro. Subsequently, combinatorial macros are created by merging combinatorial signal cones along unit signal paths.

Abstract: The invention relates to a method and a system for placing macros of a multilevel hierarchical description of a design unit on a chip. The method starts off by repartitioning the macro structure of the design unit into a set of latch macros and a set of combinatorial macros. By definition, a combinatorial macro is constructed in such a way that it contains no latches, and a latch macro contains latches and is constructed in such a way that each primary input/output of the latch macro coincides with an input or an output of a latch within said latch macro. After repartitioning the macro structure, the latch macros are synthesized within temporary boundaries and placed on the chip. Subsequently, the combinatorial macros are sequentially placed within a temporary boundary and synthesized one by one.

Abstract: Systems and methods for hierarchical noise analysis of digital circuits, wherein analysis of a cell is based on the configuration of the cell itself and also the upstream circuit components that are connected to the inputs of the cell. One embodiment comprises a method for noise analysis in an electronic circuit such as a digital CMOS circuit. The method includes identifying a cell and identifying the inputs of the cell. For each of the inputs of the cell, a corresponding first upstream circuit component is identified. The identified component is the first component upstream from the cell's input and is directly connected to the input. A noise analysis for the cell is performed based upon the configuration of the cell in combination with the identified upstream circuit components. The result of the analysis for the combination of the cell and the upstream circuit components can then be stored.